Ketogenic – or keto as it is more commonly known – is really a lifestyle: a way of eating, thinking about and experiencing food. The Ketogenic Kitchen shows you how to approach this lifestyle – you can get into it slowly or dive straight in; it’s up to you.
The main goal of the ketogenic diet is to teach the body to run on fat instead of glucose, so all carbohydrates are severely restricted and are instead replaced with fats in the form of oils, dairy, oily fish, avocadoes, nuts and seeds.
But as with any regime that brings change on this scale, there are important points to note and also some key contraindications. And while many of the contraindications are pretty obscure, it’s essential to know what they are, just in case. The book summarises them, but we look at them in closer detail below.
High fat, not high protein
Keto is a clinically proven method of weight loss, but it also holds much promise for patients suffering from cancer, diabetes, epilepsy, neurological disorders like Multiple Sclerosis, and cardiovascular disease.
But when people hear ‘low-carb’, they immediately think ‘high-protein’, but that’s not the case with keto.
Most of what keto-ers eat is fat – in its many (and delicious!) forms. Proteins are kept at a moderate level because – and few people know this – the body will turn excess protein into sugars.
Why keto is different
Keto is unlike other ‘diets’ in one very important respect. If it is to do its job properly and switch your body to burning fat, you can’t take a ‘break’ or a ‘day off’. It’s not an 80:20 diet; it’s a metabolic therapy. Very simply, your body is either in ketosis (burning fat) or it’s not. There’s no middle ground.
And it can pose dangers, especially if it isn’t implemented correctly and no monitoring of important blood markers is being done.
It’s also important to mention that there situations where somebody absolutely shouldn’t go keto (Source: Kossoff et al (2009) Optimal clinical management of children receiving the ketogenic diet: recommendations of the International Ketogenic Diet Study Group. Epilepsia. 50(2): 304-17).
There are some medical conditions that absolutely rule out adopting a ketogenic diet. It’s quite a long list, but in reality, few nutrition clinicians see any of these conditions.
Often these conditions are diagnosed early in life, with the exception of porphyria, which can also develop later stage. So, the likelihood of having one of these conditions and not being aware of it is really small.
- Carnitine deficiency (primary)
- Carnitinepalmitoyltransferase (CPT) I or II deficiency
- Carnitinetranslocase deficiency b-oxidation defects
- Medium-chain acyl dehydrogenase deficiency (MCAD)
- Long-chain acyl dehydrogenase deficiency (LCAD)
- Short-chain acyl dehydrogenase deficiency (SCAD)
- Long-chain 3-hydroxyacyl-CoA deficiency
- Medium-chain 3-hydroxyacyl-CoA deficiency
- Pyruvate carboxylase deficiency
Health Conditions that need special attention
As well as the list above, some health conditions can make it difficult or even harmful to go into nutritional ketosis.
In these cases, it is very important to get extra support from a knowledgeable, qualified professional who understands the ins and outs of the ketogenic diet.
- Abnormalities in blood chemistry: The first step for anyone embarking on a ketogenic diet is to do a full blood count and other relevant baseline blood tests to exclude any underlying conditions. Impaired liver function, for instance, can be a problem when implementing a ketogenic diet because the liver will be in charge of producing ketone bodies and also larger amounts of bile than usual (due to the high fat intake).
- History of pancreatitis: Case studies show that elevated levels of triglycerides in the blood can lead to acute pancreatitis. Prolonged hypotension and acidosis can eventually lead to cardiac arrest.
- Active gall bladder disease: The body needs bile to break down and digest fat, and the gall bladder is responsible for storing and concentrating bile produced by the liver. There are various types of gall bladder diseases and you need professional advice before starting on the ketogenic diet.
- History of kidney failure: Although there are studies suggesting that low carb approaches can be very beneficial in renal failure, caution is advised when there are or have been issues with the kidneys.
- Poor nutritional status: If you already suffer from poor nutritional status, you definitely need individual guidance and special care. Poor nutritional status can be assessed via blood work as suggested earlier but also via physical signs. There is also a functional test called Nutreval that is outstanding when it comes to determining and analysing nutrient deficiencies.
- Gastric bypass surgery: This is obviously a unique situation where the patient needs an individualised nutrition protocol.
- Abdominal tumours and/or impaired gut function: The high fat consumption can pose a problem for patients with abdominal tumours or impaired gut function. Gut healing/an adapted form of ketogenic diets can be an option. Patricia is currently looking into a “GAPS Keto” approach for people with seriously compromised gut function.
- Decreased gastrointestinal motility: This can be caused by conventional cancer treatments and also certain medication. Because one of the first side effects of the ketogenic diet can be constipation, you need to be cautious if you suffer from this condition.
What if you have liver tumours? People with liver tumours (primary or secondary, i.e. metastatic) sometimes ask if they can do the ketogenic diet. This very much depends on liver function, which can be tested. Some people can have large tumours but still successfully manage to be in ketosis. As always, it depends on the individual!
What about safety?
Many doctors and oncologists still get a bit of a fright when they hear the word ketosis because they automatically think of “ketoacidosis”, which they were taught about in detail in college.
It’s not surprising that medical professionals confuse the two conditions, given how close they are in name and also because medical school biochemistry textbooks only briefly mention ketone metabolism.
What’s the difference between ketoacidosis and nutritional ketosis?
Diabetic ketoacidosis is a dangerous medical condition whereby blood glucose is typically higher than 13.9nmol/l (250 mg/dL), blood pH drops below 7.3 and serum bicarbonate concentration is lower than 18 meq/L. It is also common for ketone (b-hydroxybutyrate) levels to be above 15mM.
This potentially life-threatening metabolic condition is caused by a deficiency of insulin and occurs in diabetic patients (T1DM and T2DM) and occasionally also in alcohol-dependent people. Type 2 Diabetes often goes undetected for a long time, which is why it’s so important to do blood tests before embarking on any major dietary changes.
In contrast, nutritional ketosis is a natural consequence of restricting carbohydrates to under 50g/day (or fasting). A “keto-adapted” person usually has persistent low levels of blood sugar (typically between 3-4.5nmol/l or 54-81mg/dL) and elevated ketone levels (0.5-6mM).
As you can see, then, ketoacidosis doesn’t have much in common with nutritional ketosis. If your GP expresses doubts about the diet, be sure to explain this!
The No-nos: a summary
Just like any diet, the ketogenic diet takes a bit of getting used to – and for some people, it can take a while, especially if you’ve been unwell for a while and/or are overwhelmed by the options available.
If you arm yourself with the right information, however, you can be sure you are moving in the right direction. Blood tests and proper professional support are non-negotiable.
It’s also fantastic if you can bring on board those close to you, so they can offer the right encouragement and support and you can embark on the keto lifestyle with confidence!
Thanks for an excellent resource.
I have a metastasis in my gut peritoneum ( breast cancer) and I also have constipation problems. This is a life-long situation rather than due to medication alone. I am trying the keto life-style, but thought I’d just check with you to make sure it’s OK. My oncologist says ‘as long as you feel well on it it’s fine’ but of course here in the French medical world no one really knows much about nutrition and cancer!